Systems and methods for transmitting control data in a communication network

ABSTRACT

Embodiments of the present disclosure relate to a method and system for transmitting a sequence with low peak-to-average-power-ratio (PAPR). A communication system receives control data. A transmitter of the communication system comprises a plurality of sequences which are associated with the control data in the transmitter. The transmitter selects a sequence from the plurality of sequence. The selected sequence is rotated, pre-coded for generating pre-coded sequence. DFT is applied on the pre-coded sequence for generating frequency domain signals. The frequency domain signals are processed and corresponding waveform is transmitted to a receiver of the communication system. The receiver receives the waveform and is processed to extract the sequence from the waveform. The receiver correlates the extracted sequence with plurality of sequences stored in receiver memory to detect the control data. The generated waveform has low PAPR.

This application is a continuation of U.S. patent application Ser. No.16/630,674 filed Jan. 13, 2020, which claims the benefit of Indianprovisional application number 201741024935, filed on Jul. 14, 2017;Indian provisional application number 201741027870 filed on Aug. 04,2017 and Indian provisional application number 201741028728 filed onAug. 11, 2017; which hereby incorporated by reference.

TECHNICAL FIELD

Embodiments of the present disclosure are related, in general tocommunication, but specifically but not exclusively relate to method andsystem for transmitting control data having low peak-to-average powerratio (PAPR).

BACKGROUND

Presently, 5G new radio (NR) supports enhanced mobile broadband (eMBB),ultra-reliable-low-latency-communication (URLLC) andmassive-machine-type-communication (mMTC) for frequency bands below 6GHz, as well as above 6 GHz, including millimeter wave bands i.e. 20-40GHz and 60-80 GHz.

Also, ultra-low latency requires uplink control information such ashybrid automatic repeat request (ARQ) acknowledge/no-acknowledge(AC/QNACK), for the of successful decoding of block through 1-bitACK/NACK commands, and uplink sounding reference signal (SRS) to be sentto the base station with very low delay. Other control informationcomprises channel quality indicator (CQI), multiple input multipleoutput (MIMO) rank and other information.

As per the standard specifications, 5G requires a method of multiplexingcontrol, data, and SRS signals using certain waveform. The 5G NRsupports both Discrete Fourier Transform-spread-Orthogonalfrequency-division multiplexing (DFT-s-OFDM) based waveform andOrthogonal frequency-division multiplexing (OFDM) waveform for uplink.The 5G NR supports a frame structure with multiple subcarrier widths inuplink (UL) or downlink (DL). Also, 5G NR supports signals withdifferent subcarrier widths, which may be multiplexed in the of time andfrequency.

Physical Uplink Control Channel (PUCCH) carries uplink controlinformation (UCI) such as, but not limited to 1-bit hybrid automaticrepeat request (HARQ) Acknowledge (ACK)/Negative ACK (NACK), schedulingrequest (SR) and 2-bit control information. Short duration PUCCH usesthe OFDM symbol located at the end of the downlink sub-frame to convey1-2-bit feedback with low latency. The ACK/NACK are sent by the userequipment (UE) upon receiving the data from the base station (BS). TheACK represents successful reception of the data from the BS and the NACKrepresents unsuccessful reception of the data from the BS.

FIG. 1 shows a block diagram illustrating a conventional communicationsystem (100) for transmitting uplink data. As shown in FIG. 1 , thecommunication system 100 includes a Zadoff-chu (ZC) encoder 102,sub-carrier mapping module 104 and an output module 106. The ZC encoder102 is configured to receive an input data 108/control data and generatean encoded data. For example, let the input data 108 be a 2-bit controldata, which is encoded by the ZC encoder 102 to generate one of the 4Zadoff-chu (ZC) sequences. Each Zadoff-chu sequence is a cyclic shift ofa previous sequence.

The subcarrier mapping module 104 receives the ZC sequence and is mappedto a set of subcarriers to generate mapped data in frequency domain.Thereafter, the output module 106 performs the of inverse Fast Fouriertransform (IFFT) and cyclic prefix (CP) addition operations on themapped data to generate an output data 110 for transmitting.

A receiver collects the ZC frequency domain subcarriers of interest andcross correlates with each of 4-ZC sequences and selects a sequence thathas a maximum value of the cross-correlation value. Since, two bits aremapped to one of 4 sequences, the receiver can decide the bitsassociated with the ZC sequence for which the correlation value ismaximum.

The PAPR of ZC sequences is more than 3 dB. Thus, a UE requires morepower to transmit the control data using the conventional techniques.

In general, it is difficult to determine sequences that have zero crosscorrelation and have very low PAPR value. Therefore, there exists a needto design a waveform with low PAPR, so that, the PAPR delivers maximumpossible power and network link may have enhanced coverage.

The information disclosed in this background of the disclosure sectionis only for enhancement of understanding of the general background ofthe invention and should not be taken as an acknowledgement or any formof suggestion that this information forms the prior art already known toa person skilled in the art.

SUMMARY

The shortcomings of the prior art are overcome and additional advantagesare provided through the provision of method of the present disclosure.

Additional features and advantages are realized through the techniquesof the present disclosure. Other embodiments and aspects of thedisclosure are described in detail herein and are considered a part ofthe claimed disclosure.

An embodiment of the present disclosure discloses a transmitter and amethod for transmitting control data as waveforms having low peakaverage to power ratio (PAPR). The transmitter receives a control data.The transmitter comprises a plurality of sequences or code wordsrepresenting the control data. The plurality of sequences may be binaryphase shift keying (BPSK) code words. Further, the plurality ofsequences is generated such that each sequence results in a waveformthat is orthogonal to the waveforms of other sequence among theplurality of sequences. Each sequence has a predefined bit length and isassociated with control data having at least 1-bit length. Further, onesequence is selected from the plurality of sequences which correspondsto control data configured to be transmitted. The selected sequence isrotated and pre-coded to generate the pre-coded sequence. The pre-codedsequence is transformed to frequency domain pre-coded sequence byapplying DFT. Further, modulated waveform having reduced peak average topower ratio (PAPR) is generated upon processing the frequency domainpre-coded sequence. The modulated waveform is then transmitted on aPhysical Uplink Control Channel (PUCCH). In an embodiment, the waveformsare Orthogonal Frequency Division Multiplexing (OFDM) waveforms.

An embodiment of the present disclosure discloses a receiver and amethod for receiving waveforms having low PAPR. The receiver receivesone or more Orthogonal Frequency Division Multiplexed (OFDM) waveformson a PUCCH. Each of the one or more OFDM waveforms may correspond to thesequence representing control data. The sequence is associated withcontrol data having at least 1-bit length. The receiver may process theone or more OFDM waveforms for retrieving the sequence from the one ormore OFDM waveforms. The sequence is correlated with a plurality ofsequences stored in a memory associated with the receiver. The pluralityof sequences is associated with control data having at least 1-bitlength. Based on the correlation, the control data is identified.

An embodiment of the present disclosure discloses a transmitter and amethod for transmitting control data as waveforms having low peakaverage to power ratio (PAPR) in time domain. The transmitter receivescontrol data. A plurality of sequences or code words representing thecontrol data is stored in the transmitter. The input plurality ofsequences may be binary phase shift keying (BPSK) code words. Further,the plurality of sequences is generated such that each sequence resultsin a waveform that is orthogonal to the waveforms of others sequencesamong the plurality of sequences. Each sequence has a predefined bitlength and is associated with control data having at least 1-bit length.Further, one sequence is selected from the plurality of sequences whichcorresponds to control data configured to be transmitted. The selectedsequence is rotated and pre-coded to generate one pre-coded sequence.The pre-coded sequence is transformed to one frequency domain pre-codedsequence by applying DFT. Further, modulated waveform having reducedpeak average to power ratio (PAPR) is generated upon processing thefrequency domain pre-coded sequence. The modulated waveform is thentransmitted on a Physical Uplink Control Channel (PUCCH). In anembodiment, the waveforms are Orthogonal Frequency Division Multiplexing(OFDM) waveforms.

The foregoing summary is illustrative only and is not intended to be inany way limiting. In addition to the illustrative aspects, embodiments,and features described above, further aspects, embodiments, and featureswill become apparent by reference to the drawings and the followingdetailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The novel features and characteristic of the disclosure are set forth inthe appended claims. The disclosure itself, however, as well as apreferred mode of use, further objectives and advantages thereof, willbest be understood by reference to the following detailed description ofan illustrative embodiment when read in conjunction with theaccompanying figures. One or more embodiments are now described, by wayof example only, with reference to the accompanying figures wherein likereference numerals represent like elements and in which:

FIG. 1 shows a block diagram illustrating a conventional communicationsystem for transmitting data;

FIG. 2 shows an exemplary block diagram of a communication system fortransmitting control data having low PAPR in time domain, in accordancewith an embodiment of the present disclosure;

FIG. 3 shows a flow chart illustrating a method of transmitting controldata having low PAPR in a communication network, in accordance withembodiments of the present disclosure;

FIG. 4 illustrates selection of sequences corresponding to control bitconfigured to be transmitted, in accordance with embodiments of thepresent disclosure;

FIG. 5A shows a block diagram illustration of a communication system forreceiving frequency domain waveforms in a communication network, inaccordance with an embodiment of the present disclosure;

FIG. 5B shows a block diagram illustration of a communication system forreceiving time domain waveforms in a communication network, inaccordance with an embodiment of the present disclosure;

FIG. 6 shows a flow chart illustrating a method of receiving waveformsin a communication network, in accordance with embodiments of thepresent disclosure;

It should be appreciated by those skilled in the art that any blockdiagrams herein represent conceptual views of illustrative systemsembodying the principles of the present subject matter. Similarly, itwill be appreciated that any flow charts, flow diagrams, statetransition diagrams, pseudo code, and the like represent variousprocesses which may be substantially represented in computer readablemedium and executed by a computer or processor, whether or not suchcomputer or processor is explicitly shown.

DETAILED DESCRIPTION

In the present document, the word “exemplary” is used herein to mean“serving as an example, instance, or illustration.” Any embodiment orimplementation of the present subject matter described herein as“exemplary” is not necessarily to be construed as preferred oradvantageous over other embodiments.

While the disclosure is susceptible to various modifications andalternative forms, specific embodiment thereof has been shown by way ofexample in the drawings and will be described in detail below. It shouldbe understood, however that it is not intended to limit the disclosureto the particular forms disclosed, but on the contrary, the disclosureis to cover all modifications, equivalents, and alternative fallingwithin the scope of the disclosure.

The terms “comprises”, “comprising”, or any other variations thereof,are intended to cover a non-exclusive inclusion, such that a setup,device or method that comprises a list of components or steps does notinclude only those components or steps but may include other componentsor steps not expressly listed or inherent to such setup or device ormethod. In other words, one or more elements in a system or apparatusproceeded by “comprises . . . a” does not, without more constraints,preclude the existence of other elements or additional elements in thesystem or apparatus.

The Figures and the following description relate to various embodimentsby way of illustration only. It should be noted that from the followingdiscussion, alternative embodiments of the structures and methodsdisclosed herein will be readily recognized as viable alternatives thatmay be employed without departing from the principles discussed herein.Reference will now be made in detail to several embodiments, examples ofwhich are illustrated in the accompanying figures. It is noted thatwherever practicable similar or like reference numbers may be used inthe figures and may indicate similar or like functionality.

One embodiment of the present disclosure is related to generating andtransmitting waveforms having low peak average to power ratio (PAPR). Atransmitter receives a control data (for exampleacknowledgement/no-acknowledgement). The transmitter comprises aplurality of sequences or code words representing the control data.“Plurality of sequences” and “code words” are used interchangeably. Inan embodiment, a sequence is selected from the plurality of sequencesand a waveform is generated for transmitting to a receiver. Thetransmitted waveform indicates the control data configured to betransmitted. In an embodiment, the waveforms generated from theplurality of sequences are orthogonal to each other. Each sequence has apredefined length. The sequence is associated/mapped to control data(1-bit or 2-bit or N-bit). The transmitter is configured to transmit anappropriate waveform for communicating control data to a receivercommunicatively associated with the transmitter. The transmitter selectsthe sequence indicating the control data configured to be transmitted.The selected the sequence is rotated and pre-coded to generate apre-coded sequence. In an embodiment, the pre-coded sequence results ina waveform with low PAPR value. The pre-coded sequence processed togenerate corresponding modulated waveform which is then transmitted onthe PUCCH. In an embodiment, the modulated waveform is transmitted asOFDM waveform.

Another embodiment of the present disclosure is related to a receiver.The receiver receives the one or more OFDM waveforms comprising thesequence indicating control data. The receiver processes the one or moreOFDM waveforms to obtain the sequence. Thereafter, the receivercorrelates the sequence with a plurality of sequences stored in a memoryassociated with the receiver. In an embodiment, the plurality ofsequences or code words stored in the memory is generated by thereceiver, and each code word is associated with control data. Acorrelation coefficient is determined for each correlation. The sequencefrom the plurality of sequences for which the coefficient of correlationis having a peak value is identified and the corresponding control datais determined. Thus, the control data is detected by the receiver.

FIG. 2 shows a block diagram of a communication system for transmittingcontrol data in a communication network, in accordance with anembodiment of the present disclosure. The communication system 200 isalso referred as a transmitter.

As shown in FIG. 2A, the communication system 200 comprises a rotationmodule 202, a precoder 204, a discrete Fourier transform (DFT) spreadingand subcarrier mapping module 206, an inverse fast Fourier transform(IFFT) module 208 that adds CP an output module 210, a sequenceselection module 214, a processor 216 and a memory 218. In anembodiment, the processor 216 may comprise different modules forperforming various functions as disclosed in the present disclosure. Inan embodiment, the modules may comprise the sequence selection module214, the rotation module, the precoder 204, the DFT and sub-carriermapping module 206, IFFT module 208 and the output module 210. In anembodiment, the communication system 200 may be a transmitter in thisillustration. The transmitter 200 receives control data as input. Thesequence selected is indicative of associated control data. In anotherembodiment, the waveforms generated by input sequences are orthogonal toeach other. In an embodiment, for transmitting control data havinglength “N”, 2^(N) sequences or code words are generated.

For example, from the generated 2^(N) sequences, 30 groups of sequencesor code words are formed such that each group comprises 6 sequences thatresult in orthogonal waveforms. In one embodiment the 6 orthogonalwaveforms may be allocated to 3 user equipment (UE) such that each UE isprovided with 2 orthogonal waveforms. The 3 UEs may transmit controlinformation simultaneously. One of 2 orthogonal waveforms of a UE mayrepresent a control bit 1 and the other sequence may represent controlbit 0. Generally, bit 1 is associated with the control statusacknowledge (ACK) and the bit 0 is associated with control statusno-acknowledge (NACK). In an embodiment, a base station (BS) acts as amaster and each UE acts as slaves. In an embodiment, the BS may allocateeach UE with specific sequences. For example, the BS may allocate firsttwo sequences from 6 sequences to UE1 and subsequent two sequences to UE2 and remaining two sequences to UE3. The sequence selection module 214selects the sequence allocated for conveying the corresponding controlbit. A computer search is performed to generate the 30 groups ofsequences or code words. In one embodiment each BS is allocated oneindex that is the group index that takes one of 30 values and the UE isallocated sequence index that takes one of 3 values. The group andsequence indices are communicated to the UE using a control channel. Tocommunicate 2 bits comprising of the 4-bit pairs 00,01,10,11, the BS mayallocate 4 sequences to a UE that has 4 orthogonal waveforms.

The rotation module 202 performs a constellation rotation operation onthe selected sequence. In an embodiment the constellation rotation is 90degrees between successive elements of the sequence. For example,considering the input BPSK sequence is of length Q=2 for 1-bit feedback(ACK/NACK) and Q=4 for 2-bit feedback. The rotation module 202 performsj^(k) rotation on the selected sequence to generate rotated sequence.The rotated sequence is fed to a precoder 204, which pre-codes theselected rotated sequence. The precoder 204 performs one ofH(D)=1+D, where D is a delay elementH(D)=1−D.

In an embodiment, considering time domain, the precoder 204 represents acircular convolution of input with a two-tap filter, where the two tapshave equal values. The precoder 204 reduces PAPR of the waveformgenerated by the selected sequence significantly. The precoder 204output is a pre-coded data, which is fed to the DFT spreading andsub-carrier mapping module 206. The discrete Fourier transform (DFT)spreading and subcarrier mapping module 206 is also referred as a DFTmodule.

The DFT module 206 performs a DFT spreading and subcarrier mapping onthe pre-coded sequence, and the output of the DFT module is mapped tocontiguous or distributed subcarriers generating the modulatedwaveforms. The DFT module 206 performs an M-point DFT operation on asequence X, that may be defined as illustrated below:

$\begin{matrix}{{X_{k} = {\sum\limits_{i = 0}^{M - 1}{x_{n}e^{\frac{{- i}2\pi{kn}}{M}}}}},{k = 0},1,{{{2{\ldots.M}} - {1i}} = \sqrt{- 1}}} & (1)\end{matrix}$

In an embodiment, considering the precoder 204 is a 1+D precoder, thenthe DFT module 206 performs a subcarrier mapping such that the DFT istaken over the range 0, . . . , M−1, then the left half of DFT outputwill be swapped with right half. In another embodiment, if the precoder204 is a 1-D precoder and if the DFT is taken over the range 0, . . . ,M−1, then the output of the DFT module 206 output will be directlymapped to one of contiguous and distributed subcarriers. The output ofthe 210 may be referred as OFDM waveforms.

The IFFT module 208 is also referred as an inverse DFT (IDFT) module,which is configured to perform an inverse transform of the frequencydomain signals to generate a time domain signals. After an IFFToperation, the output module 210 performs the of addition of cyclicprefix, cyclic suffix, windowing, windowing with overlap and addingoperation (WOLA) on the time domain signal to generate output sequence214. A half subcarrier frequency shift may be applied to avoid DCtransmission. In an embodiment, the output sequence 214 may be fed tothe digital to analog converter to generate an analog waveform. Theoutput sequence 214 is the of 1-bit control data and 2-bit control datafor short duration physical uplink control channel (PUCCH), in anembodiment.

In an embodiment, the transmitter 200 combines pi/2 BPSK with 1+Dprecoding, to generate Quadrature Phase Shift Keying (QPSK)constellation, which is provided as input to the DFT module 206. Thereare Q-QPSK sequences with 1-1 mapping corresponding to the Q-input BPSKsequences.

In an embodiment, if the precoder 204 is configured with 1+D precoding,then left half of the M-point DFT of the QPSK sequences is swapped withthe right half, before performing subcarrier mapping. The swapping ofsubcarriers before subcarrier mapping results in 1-D precoding. Inanother embodiment, if the precoder is configured with 1-D precoding,then the M-point DFT of QPSK sequence is performed before subcarriermapping.

In an embodiment, the transmitter 200 may directly store the frequencydomain sequences or frequency domain code words generated by the DFToutputs in memory. For 1-bit control transmission the transmitterselected one of two stored frequency domain sequences and feeds thesequences to subcarrier mapping module followed by IFFT and the ofaddition of cyclic prefix, cyclic suffix, windowing, windowing withoverlap and adding operation (WOLA) on the time domain signal togenerate output sequence that may be further fed to digital to analogconverter (DAC) to generate an analog waveform. In an embodiment, for2-bit control transmission, the transmitter selected one of 4 storedfrequency domain sequences.

FIG. 3 shows a flow chart illustrating a method for generating andtransmitting low PAPR waveforms, in, in accordance with some embodimentsof the present disclosure.

As illustrated in FIG. 3 , the method 300 may comprise one or more stepsto enable generate and transmit low PAPR waveforms, in accordance withsome embodiments of the present disclosure. The method 300 may bedescribed in the general context of computer executable instructions.Generally, computer executable instructions can include routines,programs, objects, components, data structures, procedures, modules, andfunctions, which perform particular functions or implement particularabstract data types.

The order in which the method 300 is described is not intended to beconstrued as a limitation, and any number of the described method blockscan be combined in any order to implement the method. Additionally,individual blocks may be deleted from the methods without departing fromthe spirit and scope of the subject matter described herein.Furthermore, the method can be implemented in any suitable hardware,software, firmware, or combination thereof.

At step 301, an input module (not shown) of the transmitter 200 receivescontrol information. The plurality of sequences or code wordsrepresenting the control data having a predefined bit length is storedin the memory 218. Each waveform generated by the sequence is orthogonalto each other sequence.

At step 302, the sequence selection or code word selection module 214selects sequence for transmitting corresponding control bit. In anembodiment, the plurality of the sequence may be stored in a memoryassociated with the memory 218. The sequence selection module 214selects the sequence from the plurality of sequences for transmittingcontrol data that is configured to be transmitted.

At step 303, the selected the sequence is rotated to generatecorresponding rotated sequence. The rotation module 202 performs aconstellation rotation operation on the selected sequence. In anembodiment the constellation rotation is 90 degrees between successiveelements of the sequence.

At step 304, the pre-coder 204 applies pre-coding filter on the rotatedsequence to generate corresponding pre-coded sequences. In anembodiment, the pre-coder performs one of 1+D precoding or 1-Dprecoding. The pre-coded sequences have low PAPR.

At step 305, the output module 210 a is waveform is generated uponprocessing the pre-coded sequences. In an embodiment, the pre-codedsequence is passed through a DFT module 206 to generate frequency domainsequence. The frequency domain sequences are then mapped to one or moresub-carriers. In another embodiment, the frequency domain sequence,after subcarrier mapping is passed through the IFFT module 208 totransform into discrete-time domain signals. The discrete-time domainwaveforms are converted to analog signal using analog-to-digitalconverter. The output module 210 transmits the OFDM waveform on thePUCCH.

In an exemplary embodiment, Table 1 illustrates generated sequence codesusing 1-D precoding for 12 input sequences (M=12).

TABLE 1 PAPR input sequences Pi/2 BPSK after 1 + D DFT output (orfrequency (dB) (binary code word) precoding domain code word) 1.44 1 0 00 0 0 1 1 − i, −1 − i, 1 + i, −1 + i, −1 − i, 0, 0, 4.7321 − 2.7321i, −2− 2i, 0 1 1 1 0 1 − i, −1 + i, 1 + i, 1 − i, −1 + i, −4.7321 + 8.1962i,0, −4i, 7.4641 − −1 − i, 1 + i 2i, −1.2679 − 2.1962, 6 − 6i, 1.2679 +0.7321i, 0.5359 − 2i 1.86 1 0 0 0 1 0 0 1 + i, −1 − i, 1 + i, −1 + i, 1− i, 0, 2 + 0.5359i, 0.7321 + 2.7321i, 0 0 0 0 1 −1 − i, 1 + i, −1 + i,−1 − i, 1 − i, −6 − 6i, 4.7321 + 1.2679i, 1 + i, −1 − i 2 + 7.4641i, 8 +4i, 0, 1.2679 + 4.7321i, 2 − 2i, −2.7321 − 0.7321i, 0 1.44 0 0 1 0 0 0 0−1 − i, 1 − i, −1 + i, 1 + i, −1 − i, 0 − 2 − 0.5359i, 0.7321 − 1.2679,1 0 1 0 0 1 − i, 1 + i, −1 − i, −1 + i, 1 + i, −6 − 6i, −2.11962 +1.2679i, −2 − 1 − i, −1 + i 7.4641i, −4, 0, 8.1962 + 4.7321i, −2 + 2i,−2.7321 − 4.7321i, 0 1.44 1 0 1 0 1 1 1 1 + i, −1 − i, −1 + i, 1 + i, 1− i, 0, 2 + 0.5359i, 0.7321 − 1.2679i, 1 0 1 1 1 −1 + i, −1 − i, 1 − i,−1 + i, 1 = I, 6 + 6i, −2.1962 + 1.2679i, −1 − i, 1 − i 2 + 7.4641i, −4,0, 8.1962 + 4.7321i, 2 − 2i, −2.7321 − 4.7321i, 0

In an exemplary embodiment, Table 2 illustrates generated sequence codesusing 1-D precoding for 12 input sequences (M=12).

TABLE 2 input binary PAPR sequences (binary Pi/2 BPSK after 1 + D DFToutput (or frequency (dB) code word) precoding domain code word) 1.2 0 00 1 1 1 1 −1 − i, 1 − i, 1 + i, −1 − i, 1 + i, 0, 0.7321 + 0.7321i,−4.7321 − 1 0 1 0 0 −1 − i, 1 − i, −1 + i, 1 + i, 1 − i 4.7321i, 0,−8.1962 − 8.1982i, −2.7321 + 2.7321i, 0, 4.7321 − 4.7321i, 2.1962 +2.1962i, −4 + 4i, −1.2679 − 1.2679i, 1.2679 − 1.2679i 1.22 0 0 1 0 1 1 0−1 + 1, 1 − i, −1 + 1, 1 + 1, 1 − i, 0, 2.1962(1 − i), 0.7321(1 + 0), 0,0 0 1 1 1 −1 + i, 1 − i, −1 + i, −1 − i, 1 + i, 1.2679(1 + i),−8.1982(1 + i), −1 − i, 1−i −4(1 + i), −4.7321(1 − i), 4.7321(1 + i), 0,−2.7321(1 + i), −1.2679(1 − i) 1.17 0 1 1 0 0 0 1 −1 + i, 1 + i, −1 − i,1 + i, −1 − i, 0, −1.4641(1 + i), 1.1641, 0, 1 0 1 0 1 1 − i, −1 + i, 1− i, −1 + i, 1 + i, 2.5359i, 5.441(1 − i), −8, 0, 1 − i, −1 − i 9.4641i,−4(1 − i), −5.4641, 0 1.8 1 1 1 0 1 1 0 1 − i, −1 + i, −1 − i, 1 + i, 1− i, 0, −0.4641 + 1.7321 1 0 0 0 0 −+i, 1 − i, −1 − i, −1 + i, 1 − i,−3.7321 + 2.4641, 0, 4.2679 − 1 + i, −1 + i 6.4641i, 6.4641 − 1.7321i,4(1 − i), −6.4641 − 1.7321i, 7.7321 + 0.4641, 0, −0.2679 − 4.4641i,0.4641 + 1.7321i

In an exemplary embodiment, Table 3 illustrates generated sequence codesusing 1-D precoding for 12 input sequences (M=12).

TABLE 3 input sequences PAPR (input binary code Pi/2 BPSK after 1 + DDFT output (or frequency (dB) word) precoding domain code word) 1.86 0 11 1 0 1 1 −1 + i, 1 + i, −1 − i, 1 − i, 0, 0, −2(1 − i), 2(1 + i),3.4641(1 − i), 0 0 1 0 1 −1 + i, 1 + i, −1 − i, 1 + i, −1 − i, 0, −8 −4i, 5.4641(1 + i), 1 + i, 1 − i, −1 − i −3.4641(1 − i), −6(1 − i), −2(1− i), −1.4641(1 + i) 1.49 1 1 1 1 1 0 1 1 − i, −1 + i, −1 − i, 1 − i,1 + i, 0, −1.2679(1 + i), 2i, 6(1 + i), 0 1 1 1 0 −1 − i, −1 + i, 1 + i,1 − i, 3.4641, −4.7321(1 + i), −4i, −1 + i, −1 − i, 1 + i 4.7321(1 − i),−3.4641, 6(1 − i), 2i, 1.2679(1 − i) 1.48 1 1 0 1 0 0 0 1 + i, −1 + i, 1− i, −1 − i, 0, 1 + 0.2679i, 3 + 5.7321i, 0 0 0 1 1 −1 + i, 1 − i, 1 +i, −1 + i, −1 − i, −2(1 + i), 9.9282 + 5.1962i, 1 − i, −1 + 1, 1 − i 1 +3.7321i, 4i, 1 − 3.7321i, −3.9282 − 5.1962i, −1(1 − i), 3 + 2.2679i, 1 −0.2689i 1.988 0 1 1 0 0 0 1 −1 + i, 1 + i, −1 − i, 1 + i, −1 − 0,−1.4641(1 − i), 2.7321 − 0.7321i, 1 1 0 1 1 i, 1 − i, −1 + i, 1 − i, 1 +i, −1 − 2(1 + i), −1.2679 + 4.7321i, i, −1 + i, 1 − i 5.4641(1 − i),−8 + 4i, −7.4641 + 2i, −4.7321 + 1.2679i, 2(1 − i), −0.7321 + 2.7321i,−0.5359 + 2i

In exemplary embodiment Table 4 illustrates generated sequence codesusing 1-D precoding for 12 input sequences (M=12).

TABLE 4 input binary PAPR sequences (binary Pi/2 BPSK after 1 + D DFToutput (or frequency (dB) code word) precoding domain code word) 0.648810 1 1 1 1 1 −1 − i, 1 + i, −1 − i, 1 − i, 0, −1.7321 + 0.4641i, −6.4641− 1 1 1 0 0 0 1 + i, −1 + i, −1 − i, 1 − i, 1.7321i, 4(1 + i), −3 −11.1962i, 1 + i, −1 − i, 1 + i, −1 + i 1.7321 − 6.4641i, 0, −3.7321 + I,−3.0000 − 0.8038i, 0, 0.4641 + 1.7321i, −0.2679 + 1.0000i 1.5 1 0 0 1 00 1 + i, −1 − i, 1 + i, −1 − i, 0, −0.4641 + 1.7321i, 1.0000 − 1 1 1 0 01 −1 + i, 1 − i, −1 + i, 1 − i, 1.7321i, 0, −3 + 1.7321i, 6.4641 − 1 +i, −1 − i, 1 + i, −1 − i 1.7321, 4. + 12i, 6.4641 + 1.7321i, −3 −1.7321i, 0, 1. + 1.7321i, −0.4641 − 1.7321i 1.7422 1 0 1 0 0 1 1 − i, −1− i, −1 + i, 1 + i, 0, −0.7321 + 0.7321i, −0.7321 + 0 0 1 0 0 0 −1 − i,1 + i, 1 − i, −1 + i, 1 − 0.7321i, −4.0000 − 4.0000i, 1.2679 − i, −1 −i, 1 + i, −1 + i 1.2679i, 2.7321 − 2.7321i, 4.0000 − 4.0000i, 0.7321 +10.1962i, 4.7321 − 4.7321i, 4.0000 − 4.0000i, 2.7321 − 2.7321i, −2.7321− 0.1962i 1.13 1 1 1 1 0 1 1 + i, −1 + i, −1 − i, 1 − i, 0, −1.0000 −0.2679i, 3.0000 + 0 1 1 1 1 1 −1 + i, 1 + i, 1 − i, −1 − i, 1.7321i,8.0000 + 8.0000i, 1 + i, −1 + i, −1 − i, 1 − i 3.0000 + 5.1962i, −1.0000− 3.7321i, 0 − 1.0000 + 3.7321i, 3.0000 − 5.1962i, −4.0000 + 4.0000i,3.0000 − 1.7321i, −1.0000 + 0.2679i

In an exemplary embodiment Table 5 illustrates generated sequence codesusing 1-D precoding for 12 input sequences (M=12).

TABLE 5 input sequences (binary code Pi/2 BPSK after 1 + D DFT output(or frequency PAPR (dB) word) precoding domain code word) 1.476 1 0 1 11 1 1 − i, −1 − i, −1 + i, 1 − i, 1 + i, 0, 0.2679 + 1.0000i, −6.4641− 11 0 0 0 0 −1 + i, −1 − i, 1 − i, −1 + i, 1 − 0.2679i, 2.0000 + 2.0000i,i, 1 + i, −1 + i −0.4641 − 11.1962i, 3.7321 + 1.0000i, −0.0000 +4.0000i, 3.7321 − 1.0000i, 6.4641 − 0.8038i, 2.0000 − 2.0000i, 0.4641 −3.7321i, 0.2679 − 1.0000i 1.86 0 0 0 1 0 0 −1 + i, 1 − i, 1 + i, −1 − i,0, 0, 0.7321 − 2.7321i, 1 1 0 1 0 1 −1 + i, 1 − i, −1 + i, 1 − i,−2.0000 − 2.0000i, −4.7321 + −1 + i, 1 + i, 1 − i, −1 − i 1.2679i, 0,−4.0000 + 8.0000i, 7.4641 − 2.0000i, −1.2679 + 4.7321i, −6.0000 +6.0000i, −2.7321 + 0.7321i, 0.5359 − 2.0000i 0.97 1 1 0 0 0 0 1 − i,−1 + i, 1 − i, −1 + i, −1 − 0, −1.9282 + 3.1962i, 1.0000 − 1 1 1 0 0 0i, 1 − i, −1 + i, 1 − i, 1 + i, 1.7321i, −2.0000 − 2.0000i, −1 − i, 1 +i, −1 + i −3.0000 + 1.7321i, 11.9282 − 7.1962i, 4.0000 + 0.0000i, 1.0000− 3.7321i, −3.0000 − 1.7321i, 2.0000 − 2.0000i, 1.0000 + 1.7321i, 1.0000− 0.2679i 1.89 0 0 1 0 0 1 −1 − i, 1 − i, −1 + i, 1 + i, −1 − 0, −1.0000− 0.2679i, −1.0000 − 1 0 1 1 0 0 i, 1 + i, −1 − i, 1 + i, 1 − i,3.7321i, −2.0000 − 2.0000i, −1 + i, 1 −i, −1 + i −6.4641 − 1.7321i,−1.0000 − 3.7321i, 4.0000 − 8.0000i, 4.4641 + 9.1962i, 0.4641 + 1.7321i,2.0000 − 2.0000i, −1.0000 − 0.2679i, −2.4641 − 1.1962i 1.86 1 1 0 1 0 11 − i, −1 + i, 1 − i, −1 − i, 0, 0, 0.7321 + 2.7321i, 0 0 0 1 0 0 −1 +i, 1 + i, 1 − i, −1 + i, −1 − −2.0000 − 2.0000i, 4.7321 − i, 1 + i, 1 −i, −1 + i, 1.2679i, 0.0000 + 0.0000i, 4.0000 − 8.0000i, 7.4641 −2.0000i, 1.51 1 0 0 1 1 0 1 − i, −1 − i, 1 + i, −1 − i, 1 + i, 0, 0.4641−1.7321i, 1.0000 − 1 0 1 1 1 0 −1 − i, −1 + i, 1 + i, 1 − i, 1.7321i,2.0000 + 2.0000i, −1 + i, −1 − i, 1 + i −3.0000 + 1.7321i, −6.4641 +1.7321i, 4.0000 + 0.0000i, 8.4641 − 5.7321i, −3.0000 − 1.7321i, 6.0000 −6.0000i, 1.0000 + 1.7321i, 1.5359 − 2.2679i 1.82 −1 1 1 1 −1 − i, 1 − i,−1 − i, 1 − i, 0, −1.0000 − 0.2679i, −1.7321 + −1 −1 1 −1 −1 + i, 1 − i,−1 + i, 1 + i, −1 − 3.0000i, −2.0000 − 2.0000i, −1 −1 1 −1 i, 1 − i,−1 + i, 1 + i 5.1962 − 3.0000i, −1.0000 − 3.7321i, −12.0000 + 0.0000i,1.0000 − 3.7321i, −5.1962 − 3.0000i, 2.0000 − 2.0000i, 1.7321 + 3.0000i,1.0000 − 0.2679i 1.4761 1 −1 1 −1 1 − i, −1 − i, −1 + i, 1 + i, −1 − 0,−1.0000 − 0.2679i, 3.7321 + −1 −1 −1 1 i, 1 − i, 1 + i, −1 − i, −1 + i,0.4641i, −2.0000 − 2.0000i, −1 1 1 −1 1 + i, −1 − i, 1 + i 0.8038 +6.4641i, −1.0000 − 3.7321i, −4.0000 + 0.0000i, 2679 − 6.4641i, 1.0000 −0.2679i 1.47 1 1 1 −1 1 + i, −1 + i, −1 − i, 1 + i, 1 − 0, 0.2679 +1.0000i, 0.4641 + 1 −1 1 −1 i, −1 − i, −1 + i, 1 + i, −1 − i, 3.7321i,2.0000 + 2.0000i, −1 1 −1 1 1 + i, 1 − i, −1 − i 6.4641 + 0.8038i,3.7321 + 1.0000i, −0.0000 − 4.0000i, 3.7321 − 1.0000i, −0.4641 +11.1962i, 2.0000 − 2.0000i, −6.4641 + 0.2679i, 0.2679 − 1.0000i 0.9762−1 1 1 1 −1 − i, 1+ i, −1 − i, 1 − i, 1 + i, 0, −3.2679 − 1.8038i,−2.0000 + 1 −1 −1 1 −1 − i, 1 + i, −1 − 1, 1 + i, 0.0000i, 2.0000 +2.0000i, 1 1 −1 −1 −1 + i, 1 − i, −1 + i 0.0000 − 3.4641i, −6.7321 −12.1962i, 4.0000 + 0.0000i, −2.7321 − 2.7321i, 0.0000 + 3.4641i,−2.0000 + 2.0000i, −2.0000 + 0.0000i, 0.7321 + 0.7321i 1.3699 1 1 1 11 + i, −1 + i, −1 − i, 1 − i, 0, −0.7321 + 0.7321i, 2.0000 + −1 1 1 1−1 + i, 1 + i, −1 − i, 1 − i, 1 + i, 0.0000i, 10.0000 + 1 1 1 1 −1 + i,−1 − i, 1 − i 10.0000i, 0.0000 + 3.4641i, 2.7321 − 2.7321i, −4.0000 +0.0000i, 2.7321 + 2.7321i, 0.0000 − 3.4641i, −2.0000 + 2.0000i, 2.0000 −0.00001, −0.7321 − 0.7321i 1.89 −1 1 −1 −1 −1 − i, 1 + i, 1 − i, −1 + i,1 − 0, 1.0000 + 0.2679i, −1.0000 − 1 1 1 1 i, −1 + i, −1 − i, 1 − i,−1 + i, 3.7321i, 2.0000 + 2.0000i, −1 1 1 −1 −1 + i, −1 − i, 1 + i−6.4641 − 1.7321i, 1.0000 + 3.7321i, −4.0000 − 8.0000i, −4.4641 −9.1962i, 0.4641 + 1.7321i, −2.0000 + 2.0000i, −1.0000 − 0.2679i,2.4641 + 1.1962i

In an exemplary embodiment, Table-6 shows 6 semi-orthogonal sequencecodes for 1+D precoding and M=12

TABLE 6 DFT output (or input binary sequences frequency domain (binarycode words) 1 + D output code word) 0 0 0 1 1 1 −1.0000 + 1.0000i 0.0000− 4.0000i 1 1 0 0 0 0 −1.0000 − 1.0000i 1.0000 − 3.7321i 1.0000 −1.0000i −6.4641 + 11.1962i 1.0000 − 1.0000i −2.0000 + 2.0000i 1.0000 −1.0000i −6.4641 + 3.7321i 1.0000 + 1.0000i 1.0000 − 0.2679i 1.0000 +1.0000i 0.0000 + 0.0000i −1.0000 − 1.0000i 1.0000 + 0.2679i −1.0000 −1.0000i 0.4641 + 0.2679i −1.0000 − 1.0000i −2.0000 − 2.0000i 1.0000 −1.0000i 0.4641 + 0.8038i 1.0000 + 1.0000i 1.0000 + 3.7321i 0 0 1 1 0 0−1.0000 − 1.0000i −4.0000 − 8.0000i 1 1 1 1 0 1 −1.0000 − 1.0000i−2.0000 + 7.4641i −1.0000 − 1.0000i −4.7321 − 1.2679i −1.0000 − 1.0000i2.0000 − 2.0000i −1.0000 − 1.0000i 0.7321 + 2.7321i −1.0000 − 1.0000i−2.0000 + 0.5359i −1.0000 − 1.0000i 0.0000 + 0.0000i −1.0000 − 1.0000i−1.4641 + 1.4641i 1.0000 − 1.0000i −2.7321 − 0.7321i 1.0000 + 1.0000i−2.0000 − 2.0000i 1.0000 + 1.0000i −1.2679 − 4.7321i 1.0000 − 1.0000i5.4641 − 5.4641i 0 1 0 1 0 1 −1.0000 + 1.0000i 4.0000 + 8.0000i 0 0 1 10 0 −1.0000 + 1.0000i −4.7321 + 4.7321i 1.0000 + 1.0000i −1.2679 +1.2679i 1.0000 − 1.0000i −2.0000 + 2.0000i −1.0000 − 1.0000i −0.7321 +0.7321i −1.0000 + 1.0000i −1.2679 + 1.2679i 1.0000 + 1.0000i 0.0000 +0.0000i 1.0000 + 1.0000i −0.7321 + 0.7321i 1.0000 + 1.0000i 2.7321 −2.7321i 1.0000 + 1.0000i −6.0000 − 6.0000i 1.0000 + 1.0000i −4.7321 +4.7321i 1.0000 + 1.0000i 2.7321 − 2.7321i 0 1 1 0 1 0 −1.0000 + 1.0000i0.0000 + 4.0000i 0 1 0 1 0 0 −1.0000 + 1.0000i −2.0000 + 7.4641i−1.0000 + 1.0000i 1.2679 + 2.1962i −1.0000 + 1.0000i −2.0000 + 2.0000i1.0000 + 1.0000i −1.2679 − 0.7321i 1.0000 − 1.0000i −2.0000 + 0.5359i1.0000 −1.0000i 0.0000 + 0.0000i 1.0000 −1.0000i 1.4641 − 1.4641i−1.0000 − 1.0000i −4.7321 + 2.7321i −1.0000 + 1.0000i −2.0000 − 2.0000i1.0000 + 1.0000i 4.7321 − 8.1962i 1.0000 + 1.0000i −5.4641 + 5.4641i 0 00 0 0 0 −1.0000 − 1.0000i 0.0000 − 4.0000i 0 0 0 0 0 1 −1.0000 − 1.0000i1.0000 − 3.7321i 1.0000 − 1.0000i 1.7321 − 3.0000i 1.0000 + 1.0000i−10.0000 + 10.0000i −1.0000 + 1.0000i 1.7321 − 1.0000i −1.0000 − 1.0000i1.0000 − 0.2679i 1.0000 − 1.0000i 0.0000 + 0.0000i 1.0000 + 1.0000i−1.0000 − 0.2679i −1.0000 + 1.0000i −1.7321 − 1.0000i −1.0000 − 1.0000i−2.0000 − 2.0000i 1.0000 − 1.0000i −1.7321 − 3.0000i 1.0000 − 1.0000i−1.0000 − 3.7321i 0 1 0 1 0 0 −1.0000 − 1.0000i −4.0000 − 8.0000i 0 1 00 1 1 −1.0000 + 1.0000i −0.0000 + 0.0000i 1.0000 + 1.0000i 3.4641 −3.4641i 1.0000 − 1.0000i −2.0000 + 2.0000i −1.0000 − 1.0000i 2.0000 −2.0000i −1.0000 − 1.0000i 0.0000 − 0.0000i 1.0000 − 1.0000i 0.0000 +0.0000i 1.0000 − 1.0000i 1.4641 − 1.4641i −1.0000 − 1.0000i 2.0000 −2.0000i −1.0000 − 1.0000i −6.0000 − 6.0000i −1.0000 − 1.0000i −3.4641 +3.4641i −1.0000 − 1.0000i −5.4641 + 5.4641i

In an exemplary embodiment, Table-7 shows 6 semi-orthogonal sequencecodes for 1-D precoding and M=12

TABLE 7 DFT output (or input binary sequences frequency domain (binarycode words) 1 − D output code word) 0 0 0 1 1 1 −1.0000 − 1.0000i0.0000 + 0.0000i 1 1 0 0 0 0 1.0000 − 1.0000i −1.7321 + 0.4641i−1.0000 + 1.0000i −3.0000 − 3.7321i 1.0000 + 1.0000i −2.0000 − 2.0000i1.0000 − 1.00001 −6.4641 − 5.1962i −1.0000 − 1.0000i 1.7321 − 6.4641i−1.0000 + 1.0000i 0.0000 + 4.0000i 1.0000 − 1.0000i −3.7321 + 1.0000i1.0000 + 1.0000i 0.4641 + 5.1962i −1.0000 − 1.0000i 6.0000 − 6.0000i1.0000 + 1.0000i −3.0000 − 0.2679i −1.0000 + 1.0000i −0.2679 + 1.0000i 00 1 1 0 0 −1.0000 − 1.0000i 0.0000 + 0.0000i 1 1 1 1 0 1 1.0000 +1.0000i −2.0000 − 0.5359i −1.0000 − 1.0000i −3.4641 + 2.0000i 1.0000 −1.0000i −2.0000 − 2.0000i −1.0000 + 1.0000i 3.4641 − 6.0000i 1.0000 +1.0000i −2.0000 − 7.4641i 1.0000 − 1.0000i 0.0000 − 4.0000i −1.0000 +1.0000i −2.0000 + 7.4641i 1.0000 − 1.0000i −3.4641 − 6.0000i −1.0000 −1.0000i −2.0000 + 2.0000i 1.0000 + 1.0000i 3.4641 + 2.0000i −1.0000 +1.0000i −2.0000 + 0.5359i 0 1 0 1 0 1 −1.0000 + 1.0000i 0.0000 + 0.0000i0 0 1 1 0 0 1.0000 + 1.0000i −0.4641 + 1.7321i 1.0000 − 1.0000i 1.7321 −4.4641i −1.0000 + 1.0000i 2.0000 + 2.0000i −1.0000 − 1.0000i −7.7321 +3.0000i 1.0000 + 1.0000i 6.4641 − 1.7321i −1.0000 − 1.0000i 0.0000 −4.0000i 1.0000 − 1.0000i −1.0000 + 3.7321i 1.0000 + 1.0000i −4.2679 +3.0000i −1.0000 + 1.0000i −6.0000 + 6.0000i 1.0000 − 1.0000i −1.7321 +2.4641i −1.0000 − 1.0000i −1.0000 + 0.2679i 0 1 1 0 1 0 1.0000 + 1.0000i0.0000 + 0.0000i 0 1 0 1 0 0 −1.0000 − 1.0000i 1.2679 + 1.2679i−1.0000 + 1.0000i 2.0000 + 0.0000i 1.0000 + 1.0000i 2.0000 + 2.0000i−1.0000 − 1.0000i 0.0000 + 3.4641i 1.0000 + 1.0000i 4.7321 + 4.7321i−1.0000 − 1.0000i −4.0000 + 0.0000i 1.0000 + 1.0000i 0.7321 + 10.1962i1.0000 − 1.0000i 0.0000 − 3.4641i −1.0000 − 1.0000i 6.0000 − 6.0000i−1.0000 + 1.0000i 2.0000 − 0.0000i 1.0000 − 1.0000i −2.7321 − 0.1962i 00 0 0 0 0 −1.0000 + 1.0000i 0.0000 + 0.0000i 0 0 0 0 0 1 1.0000 −1.0000i 1.0000 + 0.2679i 1.0000 + 1.0000i 1.7321 + 1.0000i −1.0000 +1.0000i −10.0000 − 10.0000i −1.0000 − 1.0000i 1.7321 + 3.0000i 1.0000 −1.0000i 1.0000 + 3.7321i 1.0000 + 1.0000i 0.0000 + 4.0000i −1.0000 +1.0000i −1.0000 + 3.7321i −1.0000 − 1.0000i −1.7321 + 3.0000i 1.0000 −1.0000i −2.0000 + 2.0000i 1.0000 + 1.0000i −1.7321 + 1.0000i −1.0000 −1.0000i −1.0000 + 0.2679i 0 1 0 1 0 0 1.0000 + 1.0000i 0.0000 + 0.0000i0 1 0 0 1 1 1.0000 − 1.0000i 1.4641 − 1.4641i −1.0000 + 1.0000i−4.0000 + 0.0000i 1.0000 − 1.0000i 2.0000 + 2.0000i 1.0000 + 1.0000i−0.0000 − 6.9282i −1.0000 + 1.0000i −5.4641 + 5.4641i −1.0000 − 1.0000i−4.0000 + 0.0000i 1.0000 + 1.0000i 5.4641 + 5.4641i −1.0000 − 1.0000i−0.0000 + 6.9282i 1.0000 + 1.0000i −2.0000 + 2.0000i 1.0000 − 1.0000i−4.0000 − 0.0000i −1.0000 − 1.0000i −1.4641 − 1.4641i

An embodiment of the present is disclosure is code/sequence allocationand code reuse among multiple BSs/sectors. As shown in Table 1, 12orthogonal codes have low PAPR for M=12. For 1-bit feedback, a BS mayselect a pair of orthogonal sequences while other sectors/BS may useother pairs. A total of 6 pairs of orthogonal codes may be available for12 orthogonal codes and M equal 12. For 2-bit feedback, a set of 4orthogonal codes are used in one sector/BS and other 3 such orthogonalcode sets are available for other sectors/BS.

In an embodiment, for the of 1-bit and 2-bit feedback, transmitter 200of a network may perform a code/sequence reuse across all thesectors/BSs using a configured/planned deployment. The 1-bit feedbackmay use a reuse factor 6, and 2-bit feedback may use a reuse factor 3,in an embodiment. Alternatively, a scheduler of the transmitter 200indicates the code/sequence to be used in a sector/BS.

Referring to FIG. 4 , a sequence selection module 214 is shown forselecting one sequence from two sequences generated for 1-bit feedback.Assuming that, sequence M1 is associated with bit “0” and sequence M2 isassociated with bit “1”. Both the sequences M1 and M2 are stored in thememory 218 of the transmitter 200. FIG. 4 illustrates a scenario wherebit “1” should be transmitted. The sequence selection module 214 selectsthe sequence M2 which corresponds to the bit “1”. Further, M2 isrotated, pre-coded and mapped to sub-carriers for generating OFDMwaveforms. The OFDM waveforms indicating the bit “1” is transmitted. Inanother embodiment, the DFT output sequences are stores in memory andsequence selection is done on the DFT output.

As shown in Tables 1-5, orthogonal codes/sequences codes are used forone of 1-D precoding, for M=12. The sequence codes shown in the Tables1-5, may be used for the of 1-bit and 2-bit physical uplink controlchannel (PUCCH). For 2-bit PUCCH, every sector/BS may use any one of thefour codes, shown in Tables 1 and Tables 2.

As shown in Table 6, 7 semi-orthogonal sequence codes are provided using1+D and 1-D precoding respectively, where three pairs constructed fromthe 6 codes may be used in any of the 3 sectors/BSs. The three pairs arepreferably orthogonal sequences, in an embodiment. One of the sixsequence codes is not orthogonal to that of the remaining five sequencecodes, but performance in the presence of inter sector/BS collision isfound to be acceptable. Table 4 shows a counterpart of Table 5 with 1-Dprecoding, in an embodiment of the present disclosure.

In another embodiment, Table 4 provides 6 sequence codes using 1-Dprecoding where three pairs constructed from the 6 sequence codes may beused in the three sectors/BSs. The three pairs are preferably orthogonalsequences. One sequence code, out of the six sequence codes, is notorthogonal to the remaining five sequence codes, but the correlation islow and performance in the presence of inter sector/BS collision isfound to be acceptable.

Table-6 shows 6 semi-orthogonal sequence codes for 1-D precoding andM=12.

In an embodiment, different sectors/BS, may use different set of codesgiven in the aforementioned Tables 1-4. The codes used in differentsectors/BSs may be selected from the Tables 1˜4 to provide low mutualcorrelation. The selection of codes using the Tables 1-5 may be used toconduct a search to obtain codes for other values of M as well as toobtain alternative codes.

In an embodiment, different sectors/BSs, may use different set ofsequence codes provided in the Tables 3 and 4. The sequence codes usedin different sectors/BSs may be selected to achieve low mutualcorrelation in the communication network. Also, the as shown in thetables 3 and 4, the sequence codes may be used to conduct a search toobtain the sequence codes for any value of M and obtain alternativesequence codes.

One embodiment of the present disclosure is reducing code collisionsthrough frequency orthogonality. Considering two BSs/sectors are usingone of same set of codes, and codes with high correlation, theninterference arises between the BSs/sectors. To reduce the interference,an orthogonal frequency resources is allocated in different BSs/sectors.Further, when a short PUCCH uses more than 1 OFDM symbol/waveform, theorthogonal frequency resource allocation may be used in each OFDMsymbol, however, different frequency resources may be used in differentOFDM symbols. The allocation and use of different frequency resources ineach OFDM symbol is referred as frequency hopping (FH). When differentBSs/sectors use different FH patterns, interference effects can bereduced.

In an embodiment, the Table-8 below shows 12 orthogonal sequences:

TABLE 8 BPSK input DFT output of 1 + D precoder after FFT shift (or PAPR(dB) sequences frequency domain code word) 1.476 1 −1 1 1 1 0, 0.2679 +1.0000i, −6.4641 − 0.2679i, 2.0000 + 1 1 1 −1 −1 2.0000i, −0.4641 −11.1962i, 3.7321 + 1.0000i, −0.0000 + −1 −1 4.0000i, 3.7321 − 1.0000i,6.4641 − 0.8038i, 2.0000 − 2.0000i, 0.4641 − 3.7321i, 0.2679 − 1.0000i1.86 −1 −1 −1 1 −1 0, 0, 0.7321 − 2.7321i, −2.0000 − 2.0000i, −4.7321 +−1 1 1 −1 1 1.2679i, 0, −4.0000 + 8.0000i, 7.4641 − 2.0000i, −1 1−1.2679 + 4.7321i, −6.0000 + 6.0000i, −2.7321 + 0.7321i, 0.5359 −2.0000i 0.97 1 1 −1 −1 −1 0, −1.9282 + 3.1962i, 1.0000 − 1.7321i,−2.0000 − −1 1 1 1 −1 2.0000i, −3.0000 + 1.7321i, 11.9282 − 7.1962i,4.0000 + −1 −1 0.0000i, 1.0000 − 3.7321i, −3.0000 − 1.7321i, 2.0000 −2.0000i, 1.0000 + 1.7321i, 1.0000 − 0.2679i 1.89 −1 −1 1 −1 −1 0,−1.0000 − 0.2679i, −1.0000 − 3.7321i, −2.0000 − 1 1 −1 1 1 2.0000i,−6.4641 − 1.7321i, −1.0000 − 3.7321i, −4.0000 − −1 −1 8.0000i, 4.4641 +9.1962i, 0.4641 + 1.7321i, 2.0000 − 2.0000i, −1.0000 − 0.2679i, −2.4641− 1.1962i 1.86 1 1 −1 1 −1 0, 0, 0.7321 + 2.7321i, −2.0000 − 2.0000i,4.7321 − 1 −1 −1 −1 1 1.2679i, 0.0000 + 0.0000i 4.0000 − 8.0000i, 7.4641− −1 −1 2.0000i, 1.51 1 −1 −1 1 1 0, 0.4641 − 1.7321i, 1.0000 − 1.7321i,2.0000 + −1 1 −1 1 1 2.0000i, −3.0000 + 1.7321i, −6.4641 + 1.7321i,4.0000 + 1 −1 0.0000i, 8.4641 − 5.7321i, −3.0000 − 1.7321i, 6.0000 −6.0000i, 1.0000 + 1.7321i, 1.5359 − 2.2679i 1.82 −1 1 1 1 −1 0, −1.0000− 0.2679i, −1.7321 + 3.0000i, −2.0000 − −1 1 −1 −1 −1 2.0000i, 5.1962 −3.0000i, −1.0000 − 3.7321i, −12.0000 + 1 −1 0.0000i, 1.0000 − 3.7321i,−5.1962 − 3.0000i, 2.0000 − 2.0000i, 1.7321 + 3.0000i, 1.0000 − 0.2679i1.4761 1 −1 1 −1 −1 0, −1.0000 − 0.2679i, 3.7321 + 0.4641i, −2.0000 − −1−1 1 −1 1 2.0000i, 0.8038 + 6.4641i, −1.0000 − 3.7321i, −4.0000 + 1 −10.0000i, 1.0000 − 3.7321i, 11.1962 − 0.4641i, 2.0000 − 2.0000i, 0.2679 −6.4641i, 1.0000 − 0.2679i 1.47 1 1 1 −1 1 0, 0.2679 + 1.0000i, 0.4641 +3.7321i, 2.0000 + −1 1 −1 −1 1 2.0000i, 6.4641 + 0.8038i, 3.7321 +1.0000i, −0.0000 − −1 1 4.0000i, 3.7321 − 1.0000i, −0.4641 + 11.1962i,2.0000 − 2.0000i, −6.4641 + 0.2679i, 0.2679 − 1.0000i 0.9762 −1 1 1 1 10, −3.2679 − 1.8038i, −2.0000 + 0.0000i, 2.0000 + −1 −1 1 1 1 2.0000i,0.0000 − 3.4641i, −6.7321 − 12.1962i, 4.0000 + −1 −1 0.0000i, −2.7321 −2.73211, 0.0000 + 3.4641i, −2.0000 + 2.0000i, −2.0000 + 0.0000i,0.7321 + 0.7321i 1.3699 1 1 1 1 −1 0, −0.7321 + 0.7321i, 2.0000 +0.0000i, 10.0000 + 1 1 1 1 1 10.0000i, 0.0000 + 3.4641i, 2.7321 −2.7321i, 1 1 −4.0000 + 0.0000i, 2.7321 + 2.7321i, 0.0000 − 3.4641i,−2.0000 + 2.0000i, 2.0000 − 0.0000i, −0.7321 − 0.7321i 1.89 −1 1 −1 −1 10, 1.0000 + 0.2679i, −1.0000 − 3.7321i, 2.0000 + 1 1 1 −1 1 2.0000i,−6.4641 − 1.7321i, 1.0000 + 3.7321i, −4.0000 − 1 −1 8.0000i, −4.4641 −9.1962i, 0.4641 + 1.7321i, −2.0000 + 2.0000i, −1.0000 − 0.2679i,2.4641 + 1.1962i

In an embodiment, Table-9 shows sequences generated for 1-bit controldata.

TABLE 9 Bit 0 Bit 1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 1 −1 1 1 1 1−1 −1 1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 1 1 1 −1 1 1−1 −1 1 −1 −1 −1 −1 −1 −1 −1 1 1 −1 −1 −1 −1 −1 −1 1 1 −1 −1 1 1 −1 1 1−1 −1 −1 −1 −1 1 −1 −1 1 −1 −1 −1 −1 −1 1 −1 1 −1 −1 −1 −1 −1 1 1 −1 −1−1 −1 −1 1 −1 1 −1 −1 −1 −1 −1 −1 1 −1 −1 −1 1 1 1 1 −1 1 −1 −1 −1 −1 −11 −1 1 −1 1 −1 −1 −1 −1 1 1 −1 −1 1 −1 −1 −1 1 1 −1 −1 −1 −1 −1 1 1 1 11 −1 −1 −1 1 −1 −1 −1 1 −1 −1 1 −1 −1 −1 −1 −1 −1 −1 1 1 1 −1 −1 −1 −1−1 −1 1 −1 −1 1 −1 1 −1 −1 −1 1 1 −1 −1 −1 −1 1 1 1 1 −1 1 −1 −1 −1 1 −1−1 −1 1 1 1 −1 1 1 1 −1 −1 −1 1 −1 −1 1 −1 −1 1 −1 −1 −1 1 1 1 −1 1 1 1−1 −1 −1 1 −1 −1 −1 1 −1 1 −1 −1 −1 −1 −1 −1 1 −1 −1 −1 1 −1 1 −1 1 −1−1 −1 −1 −1 −1 1 −1 1 −1 −1 −1 1 −1 −1 −1 1 1 1 1 −1 1 −1 −1 1 1 −1 −1−1 −1 1 −1 1 1 1 1 −1 −1 −1 1 −1 −1 −1 1 1 −1 1 −1 −1 −1 1 −1 −1 −1 1 1−1 1 1 −1 −1 −1 −1 1 −1 1 −1 −1 −1 −1 1 −1 1 −1 −1 −1 −1 −1 1 1 1 1 1 −11 −1 −1 1 −1 1 −1 1 −1 1 1 1 −1 1 1 −1 −1 1 −1 −1 −1 −1 1 1 1 −1 −1 1 −1−1 1 1 −1 −1 −1 −1 −1 1 −1 −1 −1 1 −1 −1 1 −1 1 1 1 −1 1 −1 −1 −1 −1 1−1 1 1 1 1 −1 1 −1 −1 1 −1 1 −1 −1 1 −1 −1 −1 −1 1 1 1 1 1 1 1 1 −1 1 11 −1 −1 1 −1 1 −1 1 1 −1 1 −1 −1 1 1 1 −1 1 −1 1 −1 1 −1 −1 1 −1 −1 1 −11 1 1 −1 1 1 −1 −1 1 1 −1 1 −1 1 1 −1 −1 −1 1 −1 −1 −1 1 −1 1 1 1 1 1 −1−1 1 −1 1 −1 1 1 1 −1 1 −1 1 −1 1 −1 −1 1 1 −1 −1 −1 −1 −1 −1 −1 1 −1 −1−1 1 1 −1 −1 −1 1 1 −1 1 −1 −1 1 1 −1 1 −1 1 −1 −1 −1 −1 1 1 1 −1 1 1 1−1 −1 1 1 −1 −1 −1 1 1 1 1 −1 −1 −1 1 −1 1 −1 −1 1 −1 1 1 −1 1 1 1 1 1−1 1 −1 −1 −1 −1 1 −1 1 −1 −1 1 −1 −1 −1 1 −1 1 1 1 1 −1 −1 1 −1 1 −1 −1−1 −1 1 1 −1 1 −1 1 −1 1 1 1 −1 1 −1 −1 −1 −1 −1 1 −1 1 −1 −1 1 1 1 1 1−1 −1 1 −1 1 −1 −1 −1 −1 1 −1 1 −1 −1 −1 −1 1 −1 1 1 −1 1 1 1 −1 −1 1 1−1 1 −1 −1 −1 −1 1 1 1 −1 −1 1 −1 1 1 1 −1 −1 1 1 −1 1 1 1 −1 1 −1 −1 −1−1 1 1 −1 −1 −1 1 1 −1 1 1 −1 −1 −1 1 −1 1 1 1 −1 −1 1 −1 1 1 −1 1 1 1 11 1 1 1 1 −1 1 1 1 −1 1 1 1 1 1 1 1 −1 −1 −1 1 −1 1

In an embodiment, Table-10 shows sequences generated for 2-bit controldata.

TABLE 10 Bit 00 Bit 01 −1 −1 −1 −1 −1 −1 −1 1 −1 1 −1 −1 1 −1 −1 1 1 −1−1 −1 −1 −1 1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 −1 1 −1 −1 1 −1 1 1 11 1 −1 1 −1 −1 −1 −1 −1 −1 −1 1 −1 −1 −1 −1 1 −1 −1 1 1 −1 1 1 −1 1 −1 1−1 −1 −1 −1 −1 −1 −1 1 1 −1 −1 1 −1 1 −1 −1 −1 −1 −1 −1 1 1 −1 −1 −1 −1−1 −1 −1 −1 1 −1 −1 −1 −1 −1 −1 1 −1 −1 −1 1 −1 1 −1 1 1 −1 −1 −1 −1 −1−1 −1 1 −1 1 −1 −1 −1 −1 −1 −1 1 −1 1 −1 1 −1 −1 −1 1 −1 −1 −1 −1 −1 −11 −1 1 −1 −1 −1 −1 1 −1 −1 −1 −1 −1 1 1 1 −1 −1 −1 −1 −1 −1 −1 1 −1 −1 1−1 −1 −1 1 −1 −1 1 −1 1 −1 1 −1 −1 1 1 −1 −1 −1 −1 −1 1 1 −1 −1 −1 −1 −1−1 −1 1 −1 −1 1 1 1 −1 −1 −1 −1 −1 −1 −1 −1 1 −1 −1 −1 1 −1 −1 −1 1 1 −11 1 −1 1 −1 −1 1 −1 −1 −1 −1 −1 −1 1 1 −1 1 1 1 −1 −1 1 −1 1 1 1 −1 1 −1−1 1 1 −1 Bit 10 Bit 11 −1 1 −1 1 −1 1 −1 −1 −1 −1 −1 1 −1 1 −1 1 1 1 11 −1 1 1 −1 −1 1 −1 1 −1 −1 1 1 −1 1 −1 1 1 1 −1 −1 −1 −1 1 −1 −1 1 −1−1 −1 1 −1 1 −1 1 −1 −1 −1 1 −1 1 1 1 −1 −1 1 1 1 −1 −1 −1 −1 −1 −1 1 −11 −1 1 1 1 1 1 −1 1 1 −1 −1 1 −1 −1 −1 1 −1 1 1 1 −1 −1 1 −1 1 −1 1 1 1−1 −1 1 −1 −1 1 −1 −1 −1 1 1 1 −1 −1 −1 −1 −1 1 1 −1 −1 −1 1 −1 −1 −1 1−1 1 −1 1 −1 −1 1 1 1 −1 1 −1 −1 1 −1 −1 −1 1 −1 1 −1 −1 −1 1 1 1 −1 −11 1 −1 1 −1 1 1 1 −1 1 −1 1 −1 −1 −1 1 1 1 −1 1 1 1 −1 −1 −1 −1 −1 −1 −11 1 −1 −1 −1 −1 1 1 −1 1 −1 −1 1 −1 1 −1 1 −1 1 −1 1 −1 1 1 1 −1 1 −1 1−1 1 1 1 −1 1 1 1 −1 1 1 −1 −1 −1 1 1 1 1 −1 −1 −1 1 −1 1 1 −1 −1 1 −1 1−1 −1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 −1 1 1 1 1 1 1 1 1 1 1 −1−1 −1 −1 −1 1 1

In an embodiment, for 1-bit case, Table-9 gives 30 base sequences eachwith a pair of sequences to indicate 1-bit. For 2-bit case, Table-10gives 11 base sequences each base has 4 sequences to indicate 2 bits.

FIG. 5 shows a block diagram illustration of a receiver 500 forreceiving short duration physical uplink control channel (PUCCH) thatemploys non-coherent detection technique, in accordance with anembodiment of the present disclosure.

As shown in FIG. 5A, the communication system 500 includes a processor502, and memory 504. The communication system 500 is also referred asreceiver 500. The memory 504 may be communicatively coupled to theprocessor 502. The processor 502 may be configured to perform one ormore functions of the receiver 500 for receiving data. In oneimplementation, the receiver 500 may comprise modules 506 for performingvarious operations in accordance with the embodiments of the presentdisclosure.

The modules 506 includes a DFT filtering module 508, a subcarrierde-mapping module 510, and a cross correlation module 512. The filteringmodule 508 receives an input data 516, generated by a communicationsystem/transmitter 200, and performs DFT filtering of the received inputdata 516 to generate filtered sequence. The input data 516 may be a 1-2bit sequence associated with the short duration PUCCH.

The subcarrier de-mapping module 510 performs de-mapping of the filteredsequence to produce de-mapped sequence. The cross-correlation module 512performs frequency domain cross correlation on the de-mapped sequence todetermine the 1-2 bit sequence transmitted by the transmitter 200.

In an embodiment, consideringz _(p,k) =h _(p,k) R _(m,k) +N _(p,k) , k=0,1,2, . . . M−1 p=1,2, . . .N _(r)

where z_(p,k) denote the received signal at the p th antenna,considering there are N_(r) antennas for the receiver 500, of kthsubcarrier, after subcarrier de-mapping.

R_(m,k) is the m th frequency domain sequence or code word, consideringthere are Q-such sequences and

k is the frequency index that takes values k=0, 1, . . . , M−1; M beingtotal number of allocated subcarriers.

h_(p,k) denotes frequency domain channel response and

N_(p,k) includes all background noise and interference signals.

In one embodiment, the receiver 500 is configured with the followingmetric in frequency domain:

${{c(m)} = {\sum\limits_{p = 1}^{N_{r}}{❘{\sum\limits_{k = 0}^{M - 1}{z_{p,k}R_{m,k}^{*}}}❘}^{2}}},{m = 1},2,{\ldots Q}$

The receiver 500 is configured such that selecting a value of m thatgives maximizes C(m) as the transmitted code word/sequence.

The modules 506 includes a filtering module 508, a subcarrier de-mappingmodule 510, inverse discrete Fourier transform (IDFT) module 552 and across correlation module 512. The filtering module 508 receives an inputdata 516, generated by a communication system or a transmitter 200,performs DFT filtering the generated filtered sequence. The input datais a 1-2 bit sequence associated with the short duration PUCCH.

The subcarrier de-mapping module 510 performs de-mapping on the filteredsequence to produce de-mapped sequence. The IDFT module 552 performsinverse DFT on the de-mapped sequence to product inverse transformedsequence or time domain sequence. The cross-correlation module 512performs cross correlation on the time domain sequence to determine the1-2 bit sequence transmitted by the transmitter 200.

In an embodiment, based on the communication system 200 or transmitter200 structure, a search is performed by the cross-correlation module 512to obtain code words/sequences that have zero cross correlation for Q=2,4 and for 1+D and 1-D precoding. The precoder with 1+D precoding resultsin a sequence with similar property, as that of 1-D precoding, afterswapping the left and right halves of DFT sequence.

An embodiment of the present disclosure may consider two receivermodules. A first receiver module is configured to apply matchedfiltering (MF) of frequency domain code i.e. one of sequences applied tothe user, on each antenna. Also, the first receiver module is configuredto performs summation of all outputs of each antenna. The summation isperformed over allocated M subcarriers to obtain a decision variable.One of the BPSK and QPSK detection is performed using the decisionvariable.

FIG. 6 illustrates a method for receiving control data on a short PUCCH.

At step 601, filtering module 508 of the receiver 500 receives the oneor more OFDM waveforms on the short PUCCH. The filtering module 508receives an input data 516, generated by a communication system or atransmitter 200, performs filtering such as, but not limited to, noiseand interference, i.e. removing the of cyclic prefix (CP), cyclic suffix(CS), windowing, windowing with overlap and adding operation (WOLA)present in the received input data 516 to generate filtered sequence.The input data is a 1-2 bit sequence associated with the short durationPUCCH. The input data 516 comprises the pre-coded waveform/sequence.

At step 602, the cross-correlation module 512 identifies the controldata associated with the pre-coded waveform/sequence.

Upon filtering the input data 516, the sub-carrier de-mapping module 510performs de-mapping of the filtered sequence to produce de-mappedsequence. Further, the cross-correlation module 512 performs frequencydomain cross correlation on the de-mapped sequence to determine the 1-2bit sequence transmitted by the transmitter 200. The correlation isperformed between the received sequence and with every sequence storedin the memory 504 of the receiver 500 to determine a coefficient. Acoefficient of correlation is determined, and a peak value ofcoefficient is used to detect the control bits.

In an embodiment, the disclosed methods and system provides reduced PAPRvalues in the communication system.

The terms “an embodiment”, “embodiment”, “embodiments”, “theembodiment”, “the embodiments”, “one or more embodiments”, “someembodiments”, and “one embodiment” mean “one or more (but not all)embodiments of the invention(s)” unless expressly specified otherwise.

The terms “including”, “comprising”, “having” and variations thereofmean “including but not limited to”, unless expressly specifiedotherwise.

The enumerated listing of items does not imply that any or all of theitems are mutually exclusive, unless expressly specified otherwise. Theterms “a”, “an” and “the” mean “one or more”, unless expressly specifiedotherwise.

A description of an embodiment with several components in communicationwith each other does not imply that all such components are required. Onthe contrary, a variety of optional components are described toillustrate the wide variety of possible embodiments of the invention.

When a single device or article is described herein, it will be readilyapparent that more than one device/article (whether or not theycooperate) may be used in place of a single device/article. Similarly,where more than one device or article is described herein (whether ornot they cooperate), it will be readily apparent that a singledevice/article may be used in place of the more than one device orarticle or a different number of devices/articles may be used instead ofthe shown number of devices or programs. The functionality and/or thefeatures of a device may be alternatively embodied by one or more otherdevices which are not explicitly described as having suchfunctionality/features. Thus, other embodiments of the invention neednot include the device itself.

The illustrated operations of FIG. 3 and FIG. 6 show certain eventsoccurring in a certain order. In alternative embodiments, certainoperations may be performed in a different order, modified or removed.Moreover, steps may be added to the above described logic and stillconform to the described embodiments. Further, operations describedherein may occur sequentially or certain operations may be processed inparallel. Yet further, operations may be performed by a singleprocessing unit or by distributed processing units.

Finally, the language used in the specification has been principallyselected for readability and instructional purposes, and it may not havebeen selected to delineate or circumscribe the inventive subject matter.It is therefore intended that the scope of the invention be limited notby this detailed description, but rather by any claims that issue on anapplication based here on. Accordingly, the disclosure of theembodiments of the invention is intended to be illustrative, but notlimiting, of the scope of the invention, which is set forth in thefollowing claims.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments will be apparent to those skilled in the art.The various aspects and embodiments disclosed herein are for purposes ofillustration and are not intended to be limiting, with the true scopeand spirit being indicated by the following claims.

The invention claimed is:
 1. A method of communication, the methodcomprising: in a transmitter: receiving a plurality of sequencesrepresenting control data; selecting a sequence from the plurality ofsequences; rotating the selected sequence to generate a pi/2 BPSKsequence; filtering the pi/2 BPSK sequence to generate a filteredsequence; transforming the filtered sequence into a frequency domainsequence by applying Discrete Fourier Transform (DFT); pre-coding thefrequency domain sequence to generate a frequency domain pre-codedsequence; generating a waveform using the frequency domain pre-codedsequence; and transmitting the waveform to a receiver.
 2. The method asclaimed in claim 1, wherein generating the waveform comprises: mappingthe frequency domain pre-coded sequence to a predefined number ofsub-carriers; and adding at least one of cyclic prefix (CP), cyclicsuffix (CS), windowing, and windowing with overlap and adding operation(WOLA).
 3. The method as claimed in claim 1, wherein generating awaveform comprises applying an Inverse Fast Fourier Transform (IFFT). 4.The method as claimed in claim 1, wherein the waveform comprises 2Nwaveforms generated for transmitting control data of length N bitswherein the value of N is 1, 2, . . . , n.
 5. The method as claimed inclaim 1, wherein the control data comprises at least one ofAcknowledgement (ACK) Negative Acknowledgement (NACK), and 1-bit controlinformation.
 6. The method as claimed in claim 1, wherein the pre-codingis performed using one of a 1+D pre-coding filter and a 1-D precodingfilter, and wherein D is a delay element.
 7. The method as claimed inclaim 1, wherein a predefined length of each sequence is
 12. 8. Themethod as claimed in claim 1, wherein four waveforms are allocated to aUE configured for transmitting control data having a length of 2 bits.9. The method as claimed in claim 1, wherein the waveform is convertedto an analog signal for transmitting as a time domain signal.
 10. Themethod as claimed in claim 1, wherein the receiver is operable to applya correlation to the waveform to detect the control data associated withthe selected sequence, wherein a peak value of a correlation coefficientis used to identify the control data.
 11. A transmitter, comprising: amemory; and a processor, communicatively coupled to the memory,configured to: receive a plurality of sequences representing controldata; select a sequence from the plurality of sequences; rotate theselected sequence to generate a pi/2 BPSK sequence; filter the pi/2 BPSKsequence to generate a filtered sequence; transform the filteredsequence into a frequency domain sequence by applying Discrete FourierTransform (DFT); pre-code the frequency domain sequence to generate afrequency domain pre-coded sequence; generate a waveform using thefrequency domain pre-coded sequence; and transmit the waveform to areceiver.
 12. The transmitter as claimed in claim 11, wherein theprocessor is configured to generate the waveform by: mapping thefrequency domain pre-coded sequence to a predefined number of sub-carriers; and adding at least one of cyclic prefix (CP), cyclic suffix(CS), windowing, and windowing with overlap and adding operation (WOLA).13. The transmitter as claimed in claim 11, wherein the processor isconfigured to generate the waveform by applying an Inverse Fast FourierTransform (IFFT).
 14. The transmitter as claimed in claim 11, whereinthe waveform comprises 2N waveforms generated for transmitting controldata of length N bits wherein the value of N is 1, 2, . . . , n.
 15. Thetransmitter as claimed in claim 11, wherein the control data comprisesat least one of Acknowledgement (ACK) Negative Acknowledgement (NACK),and 1-bit control information.
 16. The transmitter as claimed in claim11, wherein the processor is configured to pre-code using one of a 1+Dpre-coding filter and a 1-D precoding filter, and wherein D is a delayelement.
 17. The transmitter as claimed in claim 11, wherein apredefined length of each sequence is
 12. 18. The transmitter as claimedin claim 11, wherein four waveforms are allocated to a UE configured fortransmitting control data having a length of 2 bits.
 19. The transmitteras claimed in claim 11, wherein the transmitter is configured to convertthe waveform to an analog signal for transmitting as a time domainsignal.
 20. The transmitter as claimed in claim 11, wherein the receiverthat receives the waveform is operable to apply a correlation to thewaveform to detect the control data associated with the selectedsequence, wherein a peak value of a correlation coefficient is used toidentify the control data.
 21. A method of communication, the methodcomprising: in a receiver: processing a waveform comprising a frequencydomain pre-coded sequence; removing a pre-coding from the frequencydomain pre-coded sequence to generate a frequency domain sequence;transforming the frequency domain sequence into a pi/2 BPSK sequence byapplying an Inverse Discrete Fourier Transform (IDFT); and de-rotatingthe pi/2 BPSK sequence to generate a sequence representing control data.22. The method as claimed in claim 21, wherein processing the waveformcomprises: removing at least one of cyclic prefix (CP), cyclic suffix(CS), windowing, and windowing with overlap and adding operation (WOLA);and de-mapping a predefined number of sub-carriers from the frequencydomain pre-coded sequence.
 23. The method as claimed in claim 21,wherein processing the waveform comprises applying a Fast FourierTransform (FFT).
 24. The method as claimed in claim 21, wherein thewaveform comprises 2N waveforms generated for transmitting control dataof length N bits wherein the value of N is 1, 2, . . . , n.
 25. Themethod as claimed in claim 21, wherein the control data comprises atleast one of Acknowledgement (ACK) Negative Acknowledgement (NACK), and1-bit control information.
 26. The method as claimed in claim 21,wherein the pre-coding removal is based on one of a 1+D pre-codingfilter and a 1-D precoding filter, and wherein D is a delay element. 27.The method as claimed in claim 21, wherein a predefined length of eachsequence is
 12. 28. The method as claimed in claim 21, wherein fourwaveforms are allocated to a UE configured for transmitting control datahaving a length of 2 bits.
 29. The method as claimed in claim 21,wherein the waveform is converted to a digital signal for receiving as atime domain signal.
 30. The method as claimed in claim 21, wherein thereceiver is operable to apply a correlation to the waveform to detectthe control data associated with the selected sequence, wherein a peakvalue of a correlation coefficient is used to identify the control data.31. A receiver, comprising: a memory; and a processor, communicativelycoupled to the memory, configured to: receive a waveform comprising afrequency domain pre-coded sequence; remove a pre-coding from thefrequency domain pre-coded sequence to generate a frequency domainsequence; transform the frequency domain sequence into a pi/2 BPSKsequence by applying an Inverse Discrete Fourier Transform (IDFT); andde-rotate the pi/2 BPSK sequence to generate a sequence representingcontrol data.
 32. The receiver as claimed in claim 31, wherein theprocessor is configured to process the waveform by: removing at leastone of cyclic prefix (CP), cyclic suffix (CS), windowing, and windowingwith overlap and adding operation (WOLA); and de-mapping a predefinednumber of sub-carriers from the frequency domain pre-coded sequence. 33.The receiver as claimed in claim 31, wherein the receiver is configuredto process the waveform by applying a Fast Fourier Transform (FFT). 34.The receiver as claimed in claim 31, wherein the waveform comprises 2Nwaveforms generated for transmitting control data of length N bitswherein the value of N is 1, 2, . . . , n.
 35. The receiver as claimedin claim 31, wherein the control data comprises at least one ofAcknowledgement (ACK) Negative Acknowledgement (NACK), and 1-bit controlinformation.
 36. The receiver as claimed in claim 31, wherein theprocessor is configured to remove the pre-coding based on one of a 1+Dpre-coding filter and a 1-D precoding filter, and wherein D is a delayelement.
 37. The receiver as claimed in claim 31, wherein a predefinedlength of each sequence is
 12. 38. The receiver as claimed in claim 31,wherein four waveforms are allocated to a UE configured for transmittingcontrol data having a length of 2 bits.
 39. The receiver as claimed inclaim 31, wherein the receiver is configured to convert the waveform toa digital signal for receiving as a time domain signal.
 40. The receiveras claimed in claim 31, wherein the processor is operable to apply acorrelation to the waveform to detect the control data associated withthe selected sequence, wherein a peak value of a correlation coefficientis used to identify the control data.